ND16FA-6 5/8" Soft Dome Neodymium Tweeter. Unique front pressfit, flush-mount design. Center-to-center spacing as low as 1-3/8". Extended response with superior off-axis dispersion. Compact neodymium motor is effectively self-shielded. Ferrofluid enhances power handling and helps damp resonance. Don"t let the low price fool you! This versatile tweeter is a huge step above the average "budget" tweeter. Conceived with line array thoughts in mind, it is finally possible to achieve the inter-driver spacing needed to minimize comb filtering out to nearly 20 kHz. But their uses don"t stop at line arrays-- they have the sensitivity, smoothness, and power handling to individually do a two-way with most small woofers. Give them a try for your next budget or micro speaker-- you will be pleasantly surprised!